I've found that the hardest wavelength to get with grow lights is 660nm (and higher). I was wondering, how necessary is this? Like, would you be able to grow plants if you just had 435nm for Chlorophyll A and then 450nm and 630nm for Chlorophyll B with some wavelengths in between? I know the really high-end grow lights have everything you need, but I don't really want to be paying hundreds of dollars...
Plants can be grown under just the blue end of the spectrum, but they will remain much shorter than normal and will not flower. You can grow and flower plants quite nicely with led flood lights designed for home use. Bulbs rated at 3000°K are considered warm white and work well.
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